/ Dictionary / Index M mountain system: Meaning and Definition of Find definitions for: moun'tain sys"tem Pronunciation: [key] a series of interconnected or geologically related mountain ranges. Also called Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. Mountain State Mountain time Related Content Daily Word Quiz: eccentric Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language